About.com
About.com features over 600 "guides" offering original content in various areas. While About.com isn't really a search service, the guides do have extensive links to other sites -- not to mention top-notch content of their own.

Excite
Excite is one of the more popular search services on the web. It offers a fairly large index and integrates non-web material such as company information and sports scores into its results, when appropriate.

Lycos
Lycos started out as a search engine depending on listings that came from spidering the web. Then, it shifted to a directory model similar to Yahoo.

MSN Search
Microsoft's MSN Search service is a LookSmart-powered directory of web sites with secondary results that come from Inktomi.

Netscape Search
Netscape Open Directory is the foundation for Netscape Search. The Open Directory places editorial control in the hands of people who are passionate about a subject and create the best topical resources available anywhere.

Open Directory
The Open Directory uses volunteer editors to catalog the web.

Yahoo!
Yahoo has over 1 million sites listed. It supplements its results with those from Google.